Which of the following is a symptom of a knee injury?

Joint stiffness after rest is a common symptom of a knee injury. This stiffness typically occurs when the knee is held in a position for an extended period, such as during sleep or after sitting for a long time, and it can be accompanied by difficulty moving the joint upon resuming activity. This symptom reflects inflammation or damage within the joint, which may result from an injury such as a sprain, strain, meniscus tear, or ligament damage.

In contrast, increased flexibility, enhanced muscle strength, and heightened mobility range are generally not associated with knee injuries. These characteristics may indicate normal or improved function without injury, making them less relevant in the context of a knee injury diagnosis. Therefore, the presence of joint stiffness can be a significant indicator for clinicians assessing knee injuries, making it important for athletes and practitioners to recognize this symptom.